Raw materials & waste
In all our operations we look for ways to reduce our use of natural resources. We strive to substitute virgin raw materials as much as possible with alternative raw materials such as by-products from other industries.
In cement production we use waste as fuel, and industrial waste replaces some of the raw materials. In concrete production we recycle water and use fly ash in cement or in the concrete. Leftover concrete is handled in several ways to minimise waste. At some aggregates sites we recycle used asphalt.
In this way we are helping to reduce waste problems faced by municipalities and other industrial companies. At the same time, these efforts are also reducing our CO₂ emissions.
Use of alternative fuels (of total fuel consumption). Business Line Cement only
Replacing raw materials
A number of alternative raw materials are used as part of our cement production process. Fly ash is the major alternative raw material in cement production and replaces part of the carbon-intensive intermediate product clinker. We offer fly ash cement in Norway and Sweden. In Denmark we add fly ash during concrete production. In addition to limestone a number of minerals are needed for production including iron, silicon and aluminium.
A number of alternative raw materials are part of our cement production lines. Iron, silicon and aluminium are some of the minerals needed in production besides limestone, the main raw material. We now replace xx % of the additional materials with alternative resources. Due to logistics and availability this varies widely between the plants.
Fly ash is the major additive material in cement production, and replaces xx tons of clinker. We offer fly ash cements in both Norway and Sweden. In Denmark we use fly ash directly in concrete production.
Waste as energy
The use of alternative fuels is one of the most important actions we take to reduce our carbon footprint.
Our main cement plants are among the best in class in Europe when it comes to the use of alternative fuels. In 2015, the Slite plant was recognized as best in the worldwide cement industry at substituting fossil fuels.
In total 50 % of our fuels are from alternative sources, of which 38 % is classified as biomass. A variety of waste materials is utilized as fuel; wood, paper, plastics, agricultural waste, hazardous waste and more. Availability and process equipment are main factors for implementing alternative fuels.
In cement production the high temperature in the cement kiln is suitable for destruction of hazardous components. In addition, the mineral composition of the ash from the waste complements the cement quality.
Waste from our cement process that goes to landfill has been reduced significantly, mainly due to use of the by-product kiln dust in new cement products. Initiatives to reduce the landfill needed for ready mixed concrete have been successful. We have reduced overall levels of returned materials by optimising processes, and by producing block products from leftover concrete. Crushed, hardened concrete can be used as filling materials in the construction of roads.